2018-08-23
/*
* Copyright 2016, The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.architecture.blueprints.todoapp.taskdetail;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import com.example.android.architecture.blueprints.todoapp.data.Task;
import com.example.android.architecture.blueprints.todoapp.data.source.TasksDataSource;
import com.example.android.architecture.blueprints.todoapp.data.source.TasksRepository;
import com.google.common.base.Strings;
import static com.google.common.base.Preconditions.checkNotNull;
/**
* Listens to user actions from the UI ({@link TaskDetailFragment}), retrieves the data and updates
* the UI as required.
*/
public class TaskDetailPresenter implements TaskDetailContract.Presenter {
private final TasksRepository mTasksRepository;
private final TaskDetailContract.View mTaskDetailView;
@Nullable
private String mTaskId;
public TaskDetailPresenter(@Nullable String taskId,
@NonNull TasksRepository tasksRepository,
@NonNull TaskDetailContract.View taskDetailView) {
mTaskId = taskId;
mTasksRepository = checkNotNull(tasksRepository, "tasksRepository cannot be null!");
mTaskDetailView = checkNotNull(taskDetailView, "taskDetailView cannot be null!");
mTaskDetailView.setPresenter(this);
}
@Override
public void start() {
openTask();
}
private void openTask() {
if (Strings.isNullOrEmpty(mTaskId)) {
mTaskDetailView.showMissingTask();
return;
}
mTaskDetailView.setLoadingIndicator(true);
mTasksRepository.getTask(mTaskId, new TasksDataSource.GetTaskCallback() {
@Override
public void onTaskLoaded(Task task) {
// The view may not be able to handle UI updates anymore
if (!mTaskDetailView.isActive()) {
return;
}
mTaskDetailView.setLoadingIndicator(false);
if (null == task) {
mTaskDetailView.showMissingTask();
} else {
showTask(task);
}
}
@Override
public void onDataNotAvailable() {
// The view may not be able to handle UI updates anymore
if (!mTaskDetailView.isActive()) {
return;
}
mTaskDetailView.showMissingTask();
}
});
}
@Override
public void editTask() {
if (Strings.isNullOrEmpty(mTaskId)) {
mTaskDetailView.showMissingTask();
return;
}
mTaskDetailView.showEditTask(mTaskId);
}
@Override
public void deleteTask() {
if (Strings.isNullOrEmpty(mTaskId)) {
mTaskDetailView.showMissingTask();
return;
}
mTasksRepository.deleteTask(mTaskId);
mTaskDetailView.showTaskDeleted();
}
@Override
public void completeTask() {
if (Strings.isNullOrEmpty(mTaskId)) {
mTaskDetailView.showMissingTask();
return;
}
mTasksRepository.completeTask(mTaskId);
mTaskDetailView.showTaskMarkedComplete();
}
@Override
public void activateTask() {
if (Strings.isNullOrEmpty(mTaskId)) {
mTaskDetailView.showMissingTask();
return;
}
mTasksRepository.activateTask(mTaskId);
mTaskDetailView.showTaskMarkedActive();
}
private void showTask(@NonNull Task task) {
String title = task.getTitle();
String description = task.getDescription();
if (Strings.isNullOrEmpty(title)) {
mTaskDetailView.hideTitle();
} else {
mTaskDetailView.showTitle(title);
}
if (Strings.isNullOrEmpty(description)) {
mTaskDetailView.hideDescription();
} else {
mTaskDetailView.showDescription(description);
}
mTaskDetailView.showCompletionStatus(task.isCompleted());
}
}
